Strain-engineered magnon states in two-dimensional ferromagnetic monolayers

We systematically investigate the strain-engineered magnon states in two-dimensional (2D) ferromagnetic monolayers. By suitable engineering of an inhomogeneous strain, we demonstrate the emergence of magnon Landau levels and magnon snake states in 2D ferromagnetic monolayers. We show a magnon valley Hall effect and valley filter without relying on any external fields. Our proposal offers us another way to manipulate magnon valley transport and construct different types of flexible spintronic devices, and is experimentally feasible for 2D ferromagnetic materials by using state-of-art techniques.